PHP code example of skelan / simple-promise

    
        
<?php
require_once('vendor/autoload.php');

/* Start to develop here. Best regards https://php-download.com/ */

    

skelan / simple-promise example snippets

curl -sS https://getcomposer.org/installer | php

composer 

$deferred = new Skelan\SimplePromise\Deferred();

$promise = $deferred->promise();

$deferred->resolve(mixed $value = null);
$deferred->reject(mixed $reason = null);

$deferred = new Skelan\SimplePromise\Deferred();

$deferred->promise()
    ->then(function ($x) {
        // $x will be the value passed to $deferred->resolve() below
        // and returns a *new promise* for $x + 1
        return $x + 1;
    })
    ->then(function ($x) {
        // $x === 2
        // This handler receives the return value of the
        // previous handler.
        return $x + 1;
    })
    ->then(function ($x) {
        // $x === 3
        // This handler receives the return value of the
        // previous handler.
        return $x + 1;
    })
    ->then(function ($x) {
        // $x === 4
        // This handler receives the return value of the
        // previous handler.
        echo 'Resolve ' . $x;
    });

$deferred->resolve(1); // Prints "Resolve 4"

$deferred = new Skelan\SimplePromise\Deferred();

$deferred->promise()
    ->then(function ($x) {
        throw new \Exception($x + 1);
    })
    ->otherwise(function (\Exception $x) {
        // Propagate the rejection
        throw $x;
    })
    ->otherwise(function ($x) {
        echo 'Reject ' . $x->getMessage(); // 3
    });

$deferred->resolve(1);  // Prints "Reject 3"

 
try {
  return doSomething();
} catch(\Exception $e) {
    return handleError($e);
} finally {
    doFinally();  
}

$deferred = new Skelan\SimplePromise\Deferred();

$deferred->promise()
    ->then(function ($x) {
        return $x + 1;
    })
    ->then(function ($x) {
        throw new \Exception($x + 1);
    })
    ->otherwise(function (\Exception $x) { 
        //catch exception 
        var_dump('otherwise: ' . ($x->getMessage() + 1)); //4
    })
    ->always(function () { 
        //finally
        var_dump('finally ');
    });

$deferred->resolve(1); 

 
function remoteRequest() {
    $deferred = new \Skelan\SimplePromise\Deferred(function (\Skelan\SimplePromise\PromiseInterface $promise) {
        var_dump('call cancel.');
    });

    \Swoole\Timer::after(1000, function() use($deferred) {
        $deferred->resolve('finish: ' . time());
    });

    return $deferred->promise();
}

remoteRequest()->then(function ($value) {
    var_dump('resolve: ' . time());
    var_dump($value);
    throw new \Exception('xxx');
}, function($reason) {
    var_dump($reason);
})->otherwise(function(\Throwable $exception) {
    var_dump('exception: ' . $exception->getMessage());
})->always(function($value) {
    var_dump('otherwise: ' . $value);
});